Vanillin - The smell of Vanila

 
   Vanillin is a white crystalline solid with a pleasant, sweet
aroma, and a characteristic vanilla-like flavor. Chemically, it
is the methyl ether of 4-hydroxybenzoic acid, a ring compound
that contains the carboxyl (-COOH) group and the
hydroxyl (-OH) group. Vanillin is the substance responsible
for the familiar taste of vanilla, which has been used as a
food additive and spice for hundreds of years. Vanilla was
probably first used as a flavoring by the inhabitants of South
and Central America before the arrival of Europeans in the
sixteenth century. Spanish explorers brought the spice back
to Europe, where it soon became very popular as a food
additive and for the flavoring of foods. Since that time,
vanilla has become one of the world’s most popular spices.
  Vanilla is obtained naturally from the seed pod of the
tropical orchid Vanilla planifolia by a lengthy and expensive
process. The pods are picked before they ripen and then
cured until they are dark brown. The curing process involves
soaking the pods in hot water, sun-drying them, and allowing
them to ‘‘sweat’’ in straw. The cured pods are then soaked in
alcohol to produce a product known as pure vanilla extract.
The primary constituent in pure vanilla extract is vanillin,
which gives the product its flavor. The process of extracting
pure vanilla from seed pods may take as long as nine months.
Some people prefer a vanilla product that contains no, or
almost no, alcohol. If alcohol is removed, almost pure vanilla
is left behind, leaving a product known as natural vanilla
flavoring.
  Vanilla can also be extracted from plants other than
Vanilla planifolia, such as potato peels and pine tree sap.
The most economical source of the product, however, is waste
material left over from the wood pulp industry. That waste
material consists primarily of lignin, a complex natural polymer
that, along with cellulose, is the primary component of
wood. The wastes from wood pulping can be treated to break
down and separate the lignin. This leaves behind a complex
mixture, a major component of which is vanilla. This vanilla
is called lignin vanilla and has many of the same physical
properties as natural vanilla. Since it is so much less expensive
to make, it has become one of the major forms of vanilla
used by consumers. Lignin vanilla is known commercially as
artificial vanilla flavoring.
  The two forms of vanilla described earlier—natural
vanilla and lignin vanilla—are mixtures in which the compound
vanillin is a major component. In both mixtures, other
components are present in lesser amounts. These components
may add somewhat different flavors and aromas, modifying
the pure taste and smell of vanillin. Artificial methods
for the production of pure vanillin have been available since
the late 1890s. The most popular of those methods
begins with eugenol ((C3H5)C6H3(OH)OCH3) or isoeugenol
((CH3CHCH)C6H3(OH)OCH3). Either of these compounds is
then treated with acetic anhydride ((CH3CO)2O) to obtain
vanillin acetate, which is then converted to pure vanillin.
The product of this reaction, unlike natural vanilla and lignin
vanilla, is a pure compound, 4-hydroxy-3-methoxybenzaldehyde,
pure vanillin. This method was the primary method
for making artificial vanillin for more than 50 years. It has
since been replaced by an alternative method of preparation,
the Reimer-Tiemann reaction. This method for making artificial
vanillin begins with catechol (C6H4(OH)2) or guaiacol
(CH3OC6H4OH).
   The Remier-Tiemann reaction is also used to produce
another form of vanillin called ethyl vanillin. Ethyl vanillin
is the ethyl ether of 4-hydroxybenzoic acid, 4-hydroxy-
3-ethoxybenzaldehyde ((CH3CH2O)(OH)C6H3CHO). It is a close
chemical relative of natural vanillin in which the methyl
(-CH3) group of natural vanillin is replaced by an ethyl
(-CH2CH3) group. Ethyl vanillin is also known as artificial
vanilla or synthetic vanilla. Its flavor is about three times
as strong as that of methyl vanillin and is used to fortify or
replace natural vanillin and lignin vanillin.

   All forms of vanillin are used as a flavoring agent and
sweetener in many types of foods, including candies, dessert
products, ice creams, puddings, yogurts, diet shakes, and soft
drinks. It is also added to some wines, alcoholic liquors,
toothpastes, and cigarettes. The vanillins have also been
shown to stimulate one’s appetite, so they have been used
to treat appetite loss. They are also added to cattle feed to
enhance weight gain.
However, less than half the vanillin produced is used in
food products. Vanillin’s rich fragrance makes the compound
useful also as an additive in perfumes, air fresheners, soaps,
shampoos, candles, creams, lotions, colognes, and ointments.
The compound is also used as a raw material in the manufacture
of a variety of drugs, particularly the compound known
as L-dopa, used to treat Parkinson’s disease.
  Vanillin is considered safe for human consumption,
although it can be toxic in very large quantities. Known
reactions include respiratory irritation, including coughing
and shortness of breath, and gastrointestinal tract irritation.
Contact with the skin or eyes can also cause irritation, redness,
and pain. These symptoms are virtually unknown except
for individuals who work directly with the pure compounds.

Benzene-Lord of The Ring

  Benzene (BEN-zeen) is a clear, colorless liquid with an
aromatic (fragrant) odor. It occurs in coal and petroleum,
from which it is extracted for commercial use. Benzene is
very flammable, burning with a smoking flame. The compound
was discovered in 1825 by the English chemist and
physicist Michael Faraday (1791–1867), who gave the compound
the name of bicarburet of hydrogen. It was given its
modern name of benzene (benzin, at the time) by the German
chemist Eilhardt Mitscherlich (1794–1863).
The chemical structure of benzene remained one of the
great mysteries in chemistry for nearly half a century. The
compound’s formula, C6H6, suggests that it contains three
double bonds. A double bond consists of four electrons that
hold two atoms in close proximity to each other in a molecule.
Yet benzene has none of the chemical properties common
to double-bonded substances. The solution to this problem
was suggested in 1865 by the German chemist Friedrich
August Kekule´ (1829–1896). Kekule´ suggested that the six

carbon atoms in the benzene molecule are arranged in a
ring, with one hydrogen atom attached to each carbon. The
ring itself consists of three double bonds and three single
bonds, alternating with each other in the ring. The fact that

the double bonds in benzene do not act like double bonds
in other compounds was explained by the German chemist
Johannes Thiele (1860–1935), who suggested that the bonds
in benzene shift back and forth between single and double
bonds so rapidly that they are not able to behave like typical
double bonds. Chemists now use a variety of chemical formulas
for representing the character of chemical bonds in
benzene.

   Benzene is a very popular raw material for a variety of

industrial chemical reactions. In 2004, U.S. manufacturers

produced 8.8 million metric tons (9.7 million short tons) of

benzene, placing it in twelfth place among all chemicals

made in the United States that year.

  At one time, benzene was obtained from coal tar, the

thick gooey liquid left over after soft coal is converted to

coke. This method has now been largely replaced by a variety

of methods that use crude oil or refined petroleum as a raw

material. In the most popular of these methods, toluene

(C6H5CH3) from petroleum is heated over a catalyst of platinum

metal and aluminum oxide (Al2O3). The toluene loses its

methyl group (-CH3), leaving benzene as the primary product.

Other methods are available for changing the molecular

structure of hydrocarbons found in petroleum and converting

them to benzene.

   By far the most important use of benzene is as a raw

material in the synthesis of other organic compounds.

More than 90 percent of the benzene produced in the

United States is used to make ethylbenzene (55 percent),

cumene (24 percent), and cyclohexane (12 percent). The

first two compounds rank fifteenth and twentieth, respectively,

among all chemicals produced in the United States

each year. Another five percent of benzene production goes

to the synthesis of a large variety of other organic compounds,

including nitrobenzene, chlorobenzene, and maleic

anhydride, a raw material for the manufacture of plastics.

Smaller amounts of benzene are used as a solvent for

cleaning purposes, in chemical reactions, and as a gasoline

additive.

   As with most chemicals, benzene can enter the body

in one of three ways: through the skin, the nose, or the

throat. People who handle or work with benzene in their

workplaces are at greatest risk of exposure to benzene

and should take precautions in working with the material.

Because of its serious health hazards, benzene is no

longer included in most materials with which the average

person comes into contact. On those occasions when a

person does come into contact with benzene, first aid

and medical attention should be sought for treatment of

the exposure.

   The health effects of exposure to liquid benzene or

benzene fumes depends on the amount of benzene taken

into the body. The most common symptoms of benzene

exposure include irritation of the mucous membranes, convulsions,

depression, and restlessness. At greater doses, a

person may experience respiratory failure, followed by

death. Even at low concentrations, benzene can cause longterm

effects for people who are regularly in contact with

the compound. The most important of these effects are

carcinogenic. Benzene is known to cause damage to bone

marrow, resulting in a form of cancer of the blood known as

leukemia.

Gelatin

   Gelatin (JELL-ah-tin) is a mixture, not a compound. Mixtures
differ from compounds in a number of important ways.
The parts that make up a mixture are not chemically combined
with each other, as they are in a compound. Also,
mixtures have no definite composition, but consist of varying
amounts of the substances from which they are formed.
Gelatin is a mixture of water-soluble proteins with high
molecular weights. It typically occurs as a brittle solid in
the form of colorless or slightly yellow flakes or sheets, or
in powder form, with virtually no taste or odor. It absorbs up
to ten times its own weight when mixed with cold water and
dissolves in hot water. When a solution of gelatin in hot
water is cooled, it takes the form of a gel, a jelly-like material
perhaps most commonly seen as the popular dessert called
JELL-OTM. Gelatin is also available in a number of other
commercial forms, such as Knox GelatinTM, Puragel , and
Gelfoam . Gelatin has been known to humans for many
centuries, but it was not widely marketed until the late

1890s. Its name comes from the Latin word gelatus, which
means ‘‘frozen.’’

   Gelatin is made by boiling animal parts with high protein
content, such as skin, ligaments, tendons, cartilage, and
bones. The boiling process breaks down molecular bonds
between individual collagen strands in the animal tissue.
Collagen is a structural protein found in bone, cartilage,
and connective tissue. The collagen formed by this process
can be further disintegrated through additional boiling with
either acid or alkali. Type A gelatin is produced when collagen
is boiled in an acidic solution, and type B gelatin is
produced by boiling collagen in an alkaline solution.
Most of the animal parts used to make gelatin come from
cattle and pigs and are left over from meat and leather
processing. Gelatin can also be made from fish. One of the
oldest forms of gelatin is isinglass, made from the swim
bladders of fish. Jewish and Muslim dietary laws prohibit
believers from eating pork, so some gelatin is made without
pig parts. Vegetarians and vegans do not eat any animal
products, so gelatin manufacturers also make similar products
using vegetable carbohydrates, such as agar and pectin.
These vegetarian gelatins are not true gelatin, which is
always made from animal proteins.

   People discovered gelatin centuries ago and experimented
with various uses for it. In the early 1800s, for example,
gelatin was included in the food served to French soldiers as
a source of dietary proteins. In the 1890s, Knox GelatinTM
was sold as a cure for dry fingernails. Manufacturers claimed
that dry fingernails were caused by a lack of protein and that
eating gelatin would cure the condition. No scientific evidence
exists for that claim, but Knox GelatinTM became
popular among consumers nonetheless.
In 1900, the Genesee Pure Food Company began selling
flavored gelatin under the name JELL-OTM. In the early 1900s,
the company began distributing booklets containing recipes
using JELL-OTM, eventually giving out more than 15 million
such booklets. JELL-OTM eventually became one of the most

popular desserts in the United States and other countries. It has
been used to make a variety of pleasant tasting, attractive
looking dessertsmolded intomany different shapes. Cooks have
combined gelatin with water, milk, soft drinks, other liquids,
whipped toppings, or mayonnaise to change its taste and
texture. The product is often served with fruits or vegetables
as a salad. Gelatin is also combined with marshmallows, jellybeans,
jelly, yogurt, gummy candies, ice cream, and margarine
to produce desserts of many textures and flavors. The product is
sometimes recommended as a fat substitute because it provides
volume in a diet without adding many calories. Some people
include gelatin products in their diets as a way of increasing
protein intake. Although plain gelatin is almost entirely
protein, it actually has relatively little nutritional value.


Gelatin has many other uses, including:
• As a raw material for the manufacture of capsules and
gels in the production of drugs;
• As a way of holding silver halide (silver bromide and
silver iodide) crystals in place on photographic films
and plates;
• In the manufacture of blocks used to determine the
possible effects of various types of ammunition on
human flesh;

• As a binder that holds sand on sandpaper or to make
certain types of paper products (such as playing cards)
bright and shiny;
• As an additive in various types of cosmetics and skin
treatments;
• In the manufacture of meshes used in the repair of
wounds and in the production of artificial heart valves;
• In the production of certain types of cement;
• For the manufacture of light filters used in theatrical
productions and for other specialized purposes;
• As a culturing medium for bacteria;
• As a stabilizer and thickener for certain types of foods,
especially ice cream and some other dairy products;
• In the manufacture of printing inks;
• As an additive in the production of plastics and rubber
products.

Menthol

Menthol (MEN-thol) occurs naturally in the peppermint
plant. In pure form it occurs as a white crystalline material
with a cooling taste and odor. Peppermint is one of
the oldest known herbal remedies. Dried peppermint
leaves have been found in Egyptian pyramids dating to
at least 1000 BCE, and its use among the Greeks and
Romans in cooking and medical preparations is well known.
Peppermint was not introduced to western Europe, however,
until the eighteenth century, when it was used to treat a
variety of ailments ranging from toothaches to morning
sickness. It was first brought to the United States about a
century later.

   Peppermint oil is extracted from the leaves of the peppermint
plant, Mentha piperita, by steam distillation, by
which various oils in the plant are separated from each other.

   The peppermint oil is then frozen to extract the menthol
from other components of the oil. Menthol can also be produced
synthetically by the reduction of thymol [(CH3)2CHC6H3
(CH3)OH] with hydrogen.

   Menthol smells like mint and creates a soothing and
sometimes tingling sensation when it touches the skin.
Scientists theorize that menthol creates the cooling sensation
by triggering the same receptors on skin that tell the
body’s nerves to respond to cold temperatures.
The cooling sensation makes menthol a desirable additive
to aftershave lotions, skin cleansers, lotions, sore throat
lozenges, and lip balms. Menthol is also used in a variety of
cosmetics applied to the skin and medications for the relief
of itching. It is also added to foods such as chewing gums and
candies to impart a mint-like flavor.
When inhaled or ingested as a lozenge, menthol can relieve
nasal congestion and coughs, as well as cool and numb the
throat to ease the pain of sore throats. It can also be used in
ointments with camphor and eucalyptus to produce cooling and
antiseptic properties. These ointments can be applied to the
chest and/or nostrils to clear the nose and reduce coughing.
One of the most famous menthol-containing products is Vicks
VapoRub, which is used to relieve coughs and congestion.
Although menthol is soothing and cooling in small quantities,
it produces a quite different effect in larger quantities.
Gargling with a large amount ofmenthol-containing mouthwash,
for example, can create an unpleasant burning sensation.
Although menthol has been classified as a ‘‘generally
recognized as safe’’ (GRAS) product and approved for use in
foods by the U.S. Good and Drug Administration, some side
effects have been reported. On contact with the skin,
menthol may cause irritation. Ingesting large quantities can
cause abdominal pain, nausea, vomiting, dizziness, drowsiness,
and even coma. These effects are more likely to occur in
infants and children than in adults.

Testosterone : The Hormone

Men and women of all vertebrate species production
Testosterone. The current number of male body
significantly higher than the current body of the woman.
Testosterone has many biological effects in the body,
Also, a growing number of red blood cells
Muscle cells and the early development of man
Bodies. He is also responsible for the preparation of the second
On male sexual characteristics, such as the rise of the body
And Bart, increased deep voice, and sexuality
Thirst. Some of the less desirable effects include increased lubrication
Skin and acne.
Testosterone production in men to increase general
Children and reached its peak in adolescence or
More than twenty years. This reduces the other
% U2019 of human life. Testosterone shot or extreme
Levels of illness or injury, hypothalamic
Pituitary gland or testicles, it can lead to a pathological condition
such as hypogonadism.
The treatment of hypogonadism in the form of testosterone
an injection, pill, patch, gel, and the skin is available
Extent. Some people use these devices try again
People are starting to fall normally grow
elderly. Many people believe that Brown, as com-SE, the
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again lost youth. Sometimes it is advisable
also used to treat various health problems, including
Infertility, impotence, lack of libido, osteoporosis,
poor growth, anemia and anorexia. Testosterone
It can be helpful in the treatment
Conditions.
Since 1950, athletes used testosterone
Derivatives and related compounds, to improve the per-
Performance. The growth of bone and muscle specific substance u2019s%
great work to significantly increase their strength and
Resistance. Testosterone is widely
Athletes of the Soviet Union in 1950, less than
to acquire the nation% u2019s efforts to create a dominant position in the world of sport.
Performance problem with testosterone
Medicine is to increase the unwanted side effects. Usually
Decline in the growth of prostate u2019s% male
while their nuclei. It can also cause mood
That the feelings of the dangerously aggressive to understand.
Because of these side effects, researchers have developed
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Side effect. Some of these devices at birth
Testosterone production in the body after administration.
Others are of testosterone, compounds, derived Simi-
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Effects. These compounds are derivatives such as dihydro-
Testosterone, androstenedione, dehydration (known as Andro)
droepiandrosterone nandrolone (DHEA) and Clostebol. TODAY
Most derivatives of testosterone and testosterone
Compounds are prohibited in sport and
their side effects and an unfair advantage "
the benefit for the athletes who use them .supply

How You Know About Fluoride

  You know that Fluoride are contain in your toothpaste. To prevent your tooth cavity. and no harm when used at rate of 1 ppm in drinking water for the purpose of reducing tooth
decay.  but if you use for excessive, can cause nausea, vomiting, diarrhea, and cramps. Can aggravate asthma and cause severe bone changes, making movement painful. Irritant to the eyes, skin, nose, and throat.

Theobromine

Theobromine (thee-oh-BROH-meen) is a white crystalline
solid that occurs naturally in cocoa beans, from which chocolate
is obtained, and, in smaller amounts, in tea and cola nuts. Theobromine
is structurally very similar to caffeine, which differs
only in the presence of a methyl group (-CH3) on one of the
nitrogen atoms in the theobromine molecule. Both theobromine
and caffeine belong to a family of organic compounds known as
themethylxanthines. Theobromine’s effects on the human body
are similar to those of caffeine, but about ten times weaker. In
addition, caffeine is metabolized more quickly, is addictive, and
increases alertness and emotional stress. It may also have serious
effects on the central nervous system and the kidneys. By
contrast, theobromine produces feelings of well-being, is not
addictive, has no effect on the central nervous system, and
provides only gentle stimulation to the kidneys. Its effects on
the body are much longer-lasting than are those of caffeine.
  The amount of theobromine in cocoa beans varies widely,
ranging from 10 to 40 milligrams of theobromine per gram

of cocoa. The variation depends on a number of facts, including
the type of bean, the location where it was grown, and
the method of processing the bean. All chocolate products
contain theobromine, but the amount varies depending on
the type of chocolate. Dark chocolate contains significantly
more of the compound than milk chocolate, and high quality
chocolate tends to contain more theobromine than low quality
chocolate. The characteristic bitter taste of dark chocolate
is due to the theobromine present in it.

   Theobromine is usually obtained from the hulls of cocoa
beans left over after the production of chocolate. The hulls

are crushed and then treated with an absorbent, such as
water or liquid carbon dioxide, which dissolves the theobromine.
The water or carbon dioxide is then allowed to evaporate,
permitting the crystallization of the pure compound.

Water : The Most Importance substance for Life

Water is a colorless, odorless, tasteless liquid that also
occurs commonly in the solid state (as ice) and in the gaseous
state (as steamor water vapor). It is a very stable compound that
undergoes a number of important reactions. It reacts with some
metals to form elemental hydrogen and an inorganic base.With
some metals, such as sodium and potassium, the reaction is
quite violent. With other metals, such as iron, the reaction
occurs only very slowly. Water is also a weak electrolyte, ionizing
to form hydrogen ions (H+) and hydroxide ions (OH– ). The
hydrogen ions occur in solution as hydronium ions (H3O+).
Water is also a strong dipole. A dipole is a molecule in
which electrical charges are sufficiently separated from each
other that one part of the molecule is negatively charged and
another part, positively charged. Water’s dipole character is
responsible for many of its special characteristics. The positive
end of one water molecule is attracted to the negative
end of a second water molecule, resulting in the formation of
a weak (‘‘hydrogen’’) bond between the two molecules.

For example, water has a very high boiling point for a
substance with relatively small molecules. The high boiling
point is a result of the fact that heat added to water
must first be used to break hydrogen bonds between water
molecules before providing enough energy to vaporize the
molecules. Similarly, the phenomenon known as surface
tension is caused by hydrogen bonding. Surface tension
is the tendency of a liquid to act as if it is covered with a
thin film. Some insects are able to walk on water because
its surface tension is so great. The surface tension is
caused by the attractive forces between adjacent water
molecules.
   Water is also an excellent solvent. A solvent is a substance
capable of dissolving other substances. Chemists
sometimes refer to water as ‘‘the universal solvent’’ because
it is able to dissolve so many other substances. That statement
is an exaggeration, but does reflect the compound’s
ability to dissolve more substances that probably any other
single compound. Water’s ability to dissolve other substances
is at least partly a result of its strong dipole character.
The positive or negative end of a water molecule
attaches itself to the negative or positive end of the substance
to be dissolved. The force of attraction exerted by
the water molecule is sufficient to tear apart the particles of
which the second substance is composed causing them to
dissolve in the water.


     Water can be made by a variety of chemical reactions,
including:
• The oxidation of hydrogen: 2H2 + O2 ! 2H2O;
• The reaction between an acid and a base, as, for
example: NaOH + HCl ! NaCl + H2O;
• The combustion of an organic material, as, for example:
CH4 + 2O2 ! CO2 + 2H2O.
Because water occurs so abundantly, none of these
reactions is required for the commercial production of the
compound. Water makes up about 70 percent of the Earth’s
surface in the oceans, lakes, rivers, ponds, glaciers, ice caps,
and other reservoirs. The problem is that only a very small
fraction of that water—about 3 percent—is fresh water. The
remaining 97 percent is salt water. And even the 3 percent of
fresh water in lakes, rivers, and other resources is impure, in
the sense that it contains other substances dissolved and
suspended in it.
   Thus, the primary concern in obtaining adequate supplies
of pure water for household, personal, commercial,
industrial, or other uses is the purification of water, not its
synthesis. Purification of water is achieved by a number of
processes, including chlorination, filtration, distillation, or
purification by some type of ion exchange mechanism.

Activated Carbon

Activated carbon is made from any substance with

a high carbon content, and activation refers to the

development of the property of adsorption.

Activated carbon is important in purification

processes, in which molecules of various contaminants

are concentrated on and adhere to the solid

surface of the carbon. Through physical adsorption,

activated carbon removes taste and odorcausing

organic compounds, volatile organic compounds,

and many organic compounds that do not

undergo biological degradation from the atmosphere

and from water, including potable supplies,

process streams, and waste streams. The action can

be compared to precipitation. Activated carbon is

generally nonpolar, and because of this it adsorbs

other nonpolar, mainly organic, substances.

Extensive porosity (pore volume) and large available

internal surface area of the pores are responsible

for adsorption.

   Processes used to produce activated carbons

with defined properties became available only after

1900. Steam activation was patented by R. von

Ostreijko in Britain, France, Germany, and the

U.S. from 1900 to 1903. When made from wood,

the activated carbon product was called Eponite

(1909); when made from peat, it was called Norit

(1911). Activated carbon processes began in

Holland, Germany, and the U.S., and the products

were in all cases a powdered form of activated

carbon mainly used for decolorizing sugar solutions.

This remained an important use, requiring

some 1800 tons each year, into the twenty-first

century.

In the U.S., coconut char activated by steam

was developed for use in gas masks during World

War I. The advantage of using coconut shell was

that it was a waste product that could be converted

to charcoal in primitive kilns at little cost. By 1923,

activated carbon was available from black ash,

paper pulp waste residue, and lignite. In 1919, the

U.S. Public Health Service conducted experiments

on filtration of surface water contaminated with

industrial waste through activated carbon. At first,

cost considerations militated against the widespread

use of activated carbon for water treatment.

It was employed at some British works before

1930, and at Hackensack in New Jersey. From that

time there was an interest in the application of

granular activated carbon in water treatment, and

its subsequent use for this purpose grew rapidly. As

improved forms became available, activated carbon

often replaced sand in water treatment where

potable supplies were required.

   Coal-based processes for high-grade adsorbent

required for use in gas masks originally involved

prior pulverization and briquetting under pressure,

followed by carbonization, and activation. The

process was simplified after 1933 when the British

Fuel Research Station in East Greenwich, at the

request of the Chemical Research Defence

Establishment, began experiments on direct production

from coke activated by steam at elevated

temperatures. In 1940, Pittsburgh Coke & Iron

Company, developed a process for producing

granular activated carbon from bituminous coal

for use in military gas masks. During World War

II, this replaced the coconut char previously

obtained from India and the Philippines. The

large surface area created by the pores and its

mechanical hardness made this new material

particularly useful in continuous decolorization

processes. The Pittsburgh processes developed by

the Pittsburgh Activated Carbon Company were

acquired in 1965 by the Calgon Company. In late

twentieth century processes, carbon was crushed,

mixed with binder, sized and processed in lowtemperature

bakers, and subjected to high temperatures

in furnaces where the pore structure of

the carbon is developed. The activation process can

be adjusted to create pores of the required size for a

particular application. Activation normally takes

place at 800–900_C with steam or carbon dioxide.

Powdered activated carbon is suitable for liquid

and flue gas applications—the granulated form for

the liquid and gas phases, and pelleted activated

carbon for the gas phase. Granulated activated

carbon is used as a filter medium for contaminated

water or air, while the powdered form is mixed into

wastewater where it adsorbs the contaminants and

is later filtered or settled from the mixture.

Activated carbon has also been used in chemical

analysis for prior removal and concentration of

contaminants in water. Trade names for activated

carbon used in these processes are Nuchar and

Darco.

Activated carbon has been used in the largescale

treatment of liquid waste, of which the

effluent from the synthetic dye industry is a good

example. Synthetic dye manufacture involves reactions

of aromatic chemicals, and the reactants and

products are sometimes toxic. In addition to an

unpleasant taste and odor imparted to water, this

waste is also highly colored, complex, and invariably

very difficult to degrade. Fortunately, many of

the refractory aromatic compounds are nonpolar,

the property that permits adsorption onto activated

carbon. In the 1970s, three large dye-making

works in New Jersey used activated carbon to

remove aromatics and even trace metals such as

toxic lead and cadmium from liquid waste. In two

cases, powdered activated carbon was added to the

activated sludge treatment process to enhance

removal of contaminants. In a third case, following

biological treatment, the liquid effluent was

adsorbed during upward passage in towers packed

with granular activated carbon. The spent carbon

from this continuous process was regenerated in a

furnace, and at the same time the adsorbed waste

solute was destroyed.

   In 1962, Calgon utilized activated granular

carbon for treating drinking water, and at the

end of the twentieth century, municipal water

purification had become the largest market for

activated carbon. The older methods that involved

disposal of spent carbon after use were replaced by

the continuous processes using granulated activated

carbon. By continuous reuse of the regenerated

activated carbon, the process is ecologically

more desirable. Apart from the inability to remove

soluble contaminants (since they are polar) and the

need for low concentrations of both organic and

inorganic contaminants, the cost of the carbon is

the greatest limitation in the continuous process.

Activated carbon also found wide application in

the pharmaceutical, alcoholic beverage, and electroplating

industries; in the removal of pesticides

and waste of pesticide manufacture; for treatment

of wastewater from petroleum refineries and textile

factories; and for remediation of polluted groundwater.

Although activated carbons are manufactured

for specific uses, it is difficult to characterize

them quantitatively. As a result, laboratory trials

and pilot plant experiments on a specific waste type

normally precede installation of activated carbon

facilities.

Octane

Octane
Products and Uses: An antiknocking agent in internal combustion engines.
Precautions: May act as a simple asphyxiant. A narcotic in high concentrations. Extended skin contact can cause blisters. Brief skin contact causes burning sensation. A dangerous fire and explosion hazard.

Amino Acid : monomer for our protiens

amino acid An organic molecule possessing both
acidic carboxylic acid (–COOH) and basic amino
(–NH2) groups attached to the same tetrahedral carbon
atom.
Amino acids are the principal building blocks of
proteins and enzymes. They are incorporated into
proteins by transfer RNA according to the genetic
code while messenger RNA is being decoded by ribo-
somes. The amino acid content dictates the spatial
and biochemical properties of the protein or enzyme
during and after the final assembly of a protein.
Amino acids have an average molecular weight of
about 135 daltons. While more than 50 have been dis-
covered, 20 are essential for making proteins, long
chains of bonded amino acids.
Some naturally occurring amino acids are alanine,
arginine, asparagine, aspartic acid, cysteine, glutamine,
glutamic acid, glycine, histidine, isoleucine, leucine,
lysine, methionine, phenylalanine, proline, serine, thre-
onine, tryptophan, tyrosine, and valine.
The two classes of amino acids that exist are
based on whether the R-group is hydrophobic or
hydrophilic. Hydrophobic or nonpolar amino acids
tend to repel the aqueous environment and are located
mostly in the interior of proteins. They do not ionize
or participate in the formation of hydrogen bonds. On
the other hand, the hydrophilic or polar amino acids
tend to interact with the aqueous environment, are
usually involved in the formation of hydrogen bonds,
and are usually found on the exterior surfaces of pro-
teins or in their reactive centers. It is for this reason
that certain amino acid R-groups allow enzyme reac-
tions to occur.
The hydrophilic amino acids can be further subdi-
vided into polar with no charge, polar with negatively
charged side chains (acidic), and polar with positively
charged side chains (basic).

alkali metals

alkali metals (Group 1 elements) A group of soft
reactive metals, each representing the start of a new
period in the periodic table and having an electronic
configuration consisting of a rare gas structure plus one
outer electron. The metals in this group are cesium
(CS), lithium (Li), sodium (Na), potassium (K), rubid-
ium (Rb), and francium (Fr).

Acid

acid A chemical capable of donating a hydron (proton,
H+) or capable of forming a covalent bond with an elec-
tron pair. An acid increases the hydrogen ion concentra-
tion in a solution, and it can react with certain metals,
such as zinc, to form hydrogen gas. A strong acid is a
relatively good conductor of electricity. Examples of
strong acids include hydrochloric (muriatic), nitric, and
sulfuric, while examples of mild acids include sulfurous
and acetic (vinegar). The strength of an acidic solution is
usually measured in terms of its pH (a logarithmic func-
2abstractiontion of the H+ ion concentration). Strong acid solutions
have low pHs (typically around 0–3), while weak acid
solutions have pHs in the range 3–6.